Binocular stimulation and the fragmentation of after-images

Two studies were undertaken to investigate the effects of binocular stimulation on the fragmentation of after-images. Binocular after-images were produced by stimulating simultaneously, with intense flashes of light, homologous areas of the two retinas. The after-images from such stimulation were found to be more stable than those produced by monocular stimulation. A third study examined the fragmentation of after-images observed by individuals who either lacked binocular vision and stereoscopic depth perception or who had a history of difficulty with these aspects of vision. Such individuals reported far lass fragmentation than normal observers. The results are discussed in the light of research on the responses to binocular inputs of single cells in monkey occipital cortex.